Granular Compositions

ABSTRACT

Granular composition comprising 45 to 98% w/w of a water insoluble particulate, whereby 10 to 75% of the water insoluble particulate is made from a water insoluble particulate material, having a weight mean particle size of less than 20 microns and oil absorption capacity of 60 to 180 g/100 g and 10 to 75% of the water insoluble particulate is made from a water insoluble particulate material, having a weight mean particle size of below 20 microns and an oil absorption 200 to 350 g/100 g, the granular composition having a particle size, by sieve analysis, of 95% below 600 microns and 90% above 40 microns.

This application is the national phase of international applicationPCT/EP95/03560 filed Sep. 9. 1995 WO90/09033, Mar. 28, 1996 whichdesignated the U.S.

FIELD OF THE INVENTION

The present invention relates to granular compositions which provideuseful sensorially-perceived benefits in toothpaste compositions.

BACKGROUND OF THE INVENTION

The use of water as a binder for silica particles has been disclosed inGB1,365,516 and water is known as a common binder for size enlargement(Handbook of Powder Technology--Vol 1--Particle Size Enlargement--page41, Table 2.3--Elsevier).

Toothpaste formulations containing a granular composition comprising awater insoluble material and a water insoluble binder have beendisclosed in EP-B-269,966. Such granular composition can containfunctional substances such as medicaments, enzymes and polishing agents.The problem addressed by this document is that it is not possible tobind the particles within the granular composition with water solublebinders for use in formulations containing large amounts of water, suchas toothpastes. The reason being that the water soluble binder willdissolve in the aqueous component of the formulation and weaken thegranular composition making it impossible to detect the coarse particlesin the mouth.

The addition of a zinc salt, as an anti-plaque agent, into a toothpastecomposition has already been disclosed in GB 1,373,001.

It has been found that granule compositions containing only waterinsoluble particulates of low to medium structure, particularly thosewith low oil absorption capacity favored as abrasives and polishingagents in dental formulations, bound together with water and dried aretoo weak to survive the normal processes in toothpaste manufacture andtherefore would not be felt in the subsequent tooth cleaning process.

Additionally, granule compositions containing high structured waterinsoluble particulates (i.e. with high oil absorption capacity) forexample silicas favored as thickening agents in toothpaste formulations,are considered to have too much strength and give unacceptable levels ofmouthfeel.

To overcome this problem it has been discovered that granularcompositions of sufficient strength can be prepared by mixing a highstructured water insoluble particulate with a low to medium structuredone prior to the binding process. Surprisingly the addition of powderedtherapeutic agents e.g. zinc citrate, opacifiers e.g. titanium dioxideand coloured pigments have been shown to have no significant detrimentaleffect on the properties of the granular composition.

STANDARD PROCEDURES

The granular compositions of the invention are defined in terms of theproperties and texture of the water insoluble particulates used toproduce the agglomerate, its particle size distribution, and strength.

i) Oil Absorption

The oil absorption is determined by the ASTM spatula rub-out method(American Society Of Test Material Standards D, 281).

The test is based on the principle of mixing linseed oil with the waterinsoluble particulate by rubbing with a spatula on a smooth surfaceuntil a stiff putty-like paste is formed which will not break orseparate when it is cut with a spatula. The volume of oil used isconverted to weight and expressed as g of oil/100 g of water insolubleparticulate.

ii) Weight Mean Particle Size

The weight mean particle size of the water insoluble particulate beforeagglomeration is determined using a Malvern Mastersizer model X, made byMalvern Instruments, Malvern, Worcestershire with MS15 samplepresentation unit. This instrument uses the principle of mie scattering,utilising a low power He/Ne laser. The water insoluble particulates aredispersed ultrasonically in water for 5 minutes to form an aqueoussuspension and then mechanically stirred before they are subjected tothe measurement procedure outlined in the instruction manual for theinstrument, utilising a 45 mm lens in the detector system.

The Malvern Particle Sizer measures the weight particle size of thewater insoluble particulate. The weight mean particle size (d₅₀) or 50percentile, the 10 percentile (d₁₀) and the 90 percentile (d₉₀) areeasily obtained from the data generated by the instrument.

iii) Granule Composition Strength

The weight mean particle size distribution of the granular compositionis measured using the same Malvern instrument and general methoddescribed above, but with the following differences:

a) the granules are measured with a 300 mm lens in the detector system.

b) an initial particle size distribution of the granules is taken withno ultrasonic dispersion (0 ultrasonics) i.e. sample dispersed withmechanical stirring only.

c) the granules are dispersed using ultrasonics for two minutes, setting50, and then subjected to the usual measurement procedure (50ultrasonics).

d) the granules are dispersed using ultrasonics for two minutes, setting100, and then subjected to the usual measurement procedure (100ultrasonics).

The d10, d50 and d90 can then be interpolated from the particle sizedistribution generated by the instrument and the higher the valuesobtained after the exposure to ultrasonics the stronger the granularcomposition.

iv) Particle Size Distribution by Sieve Analysis

A more accurate measure of the true particle size distribution of thegranular composition is done using sieve analysis.

100 g of the sample is placed on the top sieve of a series of BS sieves,at approximately 50 micron intervals between 45 and 600 microns. Thesieves are arranged in order with the finest at the bottom and thecoarsest at the top of the stack. The sieves are placed in a mechanicalvibrator e.g. Inclyno Mechanical Sieve Shaker by Pascall Engineering CoLtd., covered with a lid and shaken for 10 minutes.

Each sieve fraction is accurately weighed and the results calculated:##EQU1## A particle size distribution can then be plotted from the data.

GENERAL DESCRIPTION OF THE INVENTION

It is a first object of the present invention to provide a granularcomposition comprising 45 to 98% w/w of a water insoluble particulate,whereby 10 to 75% of the water insoluble particulate is made from awater insoluble particulate material, having a weight mean particle sizeof less than 20 microns and an oil absorption capacity of 60 to 180g/100 g, and selected from the group consisting of amorphous silicas,aluminas, calcium carbonates, dicalcium phosphate, tribasic calciumphosphates, insoluble sodium metaphosphate, calcium pyrophosphates,hydroxyapatites, perlites, zeolites, magnesium carbonate, pumice and 10to 75% of the water insoluble particulate is made from a water insolubleparticulate material, having a weight mean particle size of below 20microns and an oil absorption 200 to 350 g/100 g, selected from thegroup consisting of amorphous silicas, low density aluminas and expandedperlites, the granular composition having a particle size, by sieveanalysis, of 95% below 600 microns and 95% above 40 microns.

This granular composition is substantially free of organic or inorganicbinder.

It is preferable that the granular composition should have a particlesize distribution, as measured by sieve analysis, such that 95% of thegranules are less than 400 microns and 95% of the particles are above100 microns, most preferably 150 microns.

Owing to the porous nature of the agglomerates, it is possible for themto act as delivery vehicles for substances that give cosmetic benefitssuch as coloring pigments, flavors, perfumes or other cosmetic. Theagglomerates can also ontain other cosmetic and/or therapeutic dentaland/or oral actives and release them into mouth. Such substances may becontained within the pores of the material. The inclusion of a materialhaving a therapeutic or cosmetic effect on the gums or teeth or oralcavity into these agglomerates provides for a further benefit in thatupon crushing or collapsing of these agglomerates, thetherapeutic/cosmetic agent is slowly released, thus delivering thetherapeutic agent over to the mouth over a longer period of time.Suitable examples of such therapeutic agents are zinc salts such as zinccitrate; antimicrobial agents such as Triclosan; anti-caries agents suchas sodium fluoride and sodium monofluorophosphate; anti-plaque agentssuch as stannous pyrophosphate etc.

In this respect it has surprisingly been found, that the inclusion ofzinc citrate in the agglomerates (in an amount of up to 15%, preferablyup to 12% by weight of the agglomerates) significantly reduced the levelof astringency, perceived by trained panellists upon testing atoothpaste with such agglomerates for their sensory properties.

The addition of TiO₂ as an opacifying agent at a concentration of 1 to5% w/w, usually at the expense of the water insoluble particulates,ensures that the granules have a white appearance and therefore standout in coloured toothpaste formulations.

If coloured granules are required, then suitable food grade colouredpigments, for example pigment dispersions under the Cosmenyl trade nameor pigment powders under the Hostaperm trade name or Cosmetic Pink RC 01(D & C Red No 30) supplied by Hoechst, can be added to the compositionof the granule, without affecting the strength of the granule.

If titanium dioxide and therapeutic agent are omitted from the granularcomposition containing abrasive and thickening silicas, then the coarseparticles are invisible in transparent gel formulations.

Moreover, the agglomerate strength can be varied over a wide range bychanging the water insoluble particulate structure, i.e. low structurewater insoluble particulates decrease strength whereas high structurewater insoluble particulates increase agglomerate strength.

The use of water insoluble particulates which already have an approvedrole in toothpastes formulations, such as toothpaste abrasive silicase.g. Sorbosil AC77 (obtainable from Crosfield Limited--England)! as thelow/medium structure component, is an added advantage since such silicasare capable of providing extra cleaning to the formulation and have goodcompatibility with the formulation. Indeed, particularly preferred waterinsoluble particulates which make up the granular composition aremixtures of synthetic, amorphous thickening e.g. Sorbosil TC15(obtainable from Crosfield Limited--England)! and abrasive silicas.

The agglomerates should be insoluble in the medium of the toothpastecomposition into which it is incorporated. In this context, "insoluble"means having insufficient solubility at ambient temperature in that theagglomerates remain undissolved or substantially undissolved in thecomposition such that their friability under the conditions of use ofthe composition and thus their ability to perform theircleaning/polishing function are not deleteriously affected. Preferably,the level of insolubility of the agglomerates extend to theirinsolubility in the oral environment in which the composition is used,which may frequently contain higher levels of water than for example atoothpaste, owing to the presence of saliva and added water frequentlyused in the brushing regime.

When the granules are incorporated in a toothpaste composition, it isimportant that they break down under the shear forces generated by thetoothbrush in a relatively short period of time, whereby the gritty feelexperienced by the user is eliminated.

This means, that the agglomerates should have a particle strength suchthat they will collapse within the range of shear and/or crush forcesnormally produced in the relevant brushing regime, since theconsiderably variable forces produced at a particular location over timeenable at least some of the agglomerates to survive intact long enoughto perform their cleaning function to a satisfactory degree.

It is even possible to tailor the breakdown time of the agglomerates,such as to control the contact time for a given duration of brushing ofthe composition, by controlling the average crush strength of theagglomerates, for example by selecting a particular type of source ofthe particulate materials and/or the manner in which they agglomerate inthe manufacturing process.

When the agglomerates break up under the action of shear and/or crushforces, the resulting average particle size (diameter) will typically beless than about 40 microns. Such reduced particle sizes will generallyavoid any feeling of grittiness in the mouth, and impart a feeling ofpolished teeth.

It is another object of the present invention to provide a process forproducing a granular composition wherein, 10 to 75 parts by weight of awater insoluble particulate material, having a weight mean particle sizeof less than 20 microns and an oil absorption capacity of 60 to 180g/100 g, and selected from the group consisting of amorphous silicas,aluminas, calcium carbonates, dicalcium phosphate, tribasic calciumphosphates, insoluble sodium metaphosphate, calcium pyrophosphates,hydroxyapatites, perlites, zeolites, magnesium carbonate, pumice aremixed with 10 to 75 parts by weight of a water insoluble particulatematerial, having a weight mean particle size of below 20 microns and anoil absorption 200 to 350 g/100 g, selected from the group consisting ofamorphous silicas, low density aluminas and expanded perlites, thenagglomerated with water, the resulting product being then dried.

Preferably, the water insoluble particulate powders are high and low tomedium structure amorphous silica particles and a therapeutic agent ismixed with them prior to agglomeration. If opaque granules are required,then TiO₂ is added to the powder mixture. If coloured granules arerequired, a suitable food grade coloured pigment dispersion can beadded.

By drying the product after agglomeration, a granular composition isobtained which is stable in a toothpaste composition.

Agglomeration can be achieved for example by pan granulation, extrusion,spray granulation or spinning disc granulation.

Preferably, the agglomeration is operated in a pan granulator, when thewater:solids (i.e. water insoluble particulates with optionally TiO₂/therapeutic agent etc. blended) ratio is in the range 1.1-1.35:1. Thisratio is important to achieve agglomerates of correct strength, sincebelow this the material remains a powder and above this a paste isformed.

Then the agglomerates are dried. This drying can be done in severalways, e.g. in an oven or in a fluidized bed. During this drying stage,the required degree of strength is built into the agglomerates.

It has also been found that agglomeration can be achieved by compactingthe powder mixture and in this process a drying stage is not required.

It is therefore another object of the present invention to provide aprocess for producing a granular composition wherein, 10 to 75 parts byweight of a water insoluble particulate material, having a weight meanparticle size of less than 20 microns and an oil absorption capacity of60 to 180 g/100 g, and selected from the group consisting of amorphoussilicas, aluminas, calcium carbonates, dicalcium phosphate, tribasiccalcium phosphates, insoluble sodium metaphosphate, calciumpyrophosphates, hydroxyapatites, perlites, zeolites, magnesiumcarbonate, pumice are mixed with 10 to 75 parts by weight of a waterinsoluble particulate material, having a weight mean particle size ofbelow 20 microns and an oil absorption 200 to 350 g/100 g, selected fromthe group consisting of amorphous silicas, low density aluminas andexpanded perlites, the resulting blend being agglomerated by compaction.

For incorporation into toothpastes, it is important that virtually allparticles are below 600 μm, preferably below 400 μm since grittyparticles give unpleasant mouthfeel properties. A size reduction steputilizing minimum energy to prevent unnecessary breakdown of theagglomerate is therefore required.

One or more sieving steps are then desirable to ensure no oversizematerial and also to provide a bottom cut at e.g. 150 microns.

SPECIFIC DESCRIPTION OF THE INVENTION

The present invention will be further illustrated in the followingexamples.

Comparative Example 1

Two silicas of high structure Sorbosil TC15 (obtainable from CrosfieldLimited--England)! and medium (bordering upon low) structure SorbosilAC77 (obtainable from Crosfield Limited--England)! were agglomeratedindividually at 200 g powder batch size, laboratory scale withde-ionised water (water:solids ratio of 1.33:1) using a Sirman CV6mixer, supplied by Metcalfe Catering Equipment Ltd, Blaenau Ffestiniog,Wales.

The resulting wet agglomerates were then dried in an oven at 150° C. for4 hours, gently forced through a 420 micron screen and sieved at 150microns to adjust the particle size distribution.

The silicas have the following properties:

    ______________________________________                     SORBOSIL  SORBOSIL    PROPERTY         TC15 (*)  AC77 (*)    ______________________________________    OIL ABSORPTION   315       120    (g/100 g)    WEIGHT MEAN  d.sub.10                         5.6       2.7    PARTICLE SIZE                 d.sub.50                         12.9      8.1    (microns)    d.sub.90                         29.3      17.8    SURFACE AREA         260       120    (m.sup.2 g.sup.-1)    ______________________________________     (*)-obtainable from Crosfield Limited  England

The granular silicas after agglomeration have the following properties:

    ______________________________________              Ultrasonics                      d10       d50    d90    ______________________________________    Sorbosil TC15                0         268       415  549                50        249       410  553                100       70        265  469    Sorbosil AC77                0         16        187  346                50        3.2       10   37.4                100       2.9       8.5  21.2    ______________________________________

The high structured silica TC15 (obtainable from CrosfieldLimited--England) forms an agglomerate which is too strong and will notbreak down in the required time with brushing in a toothpastecomposition, whilst the medium/low structured silica AC77 (obtainablefrom Crosfield Limited--England) produces an agglomerate which is tooweak to survive the normal processes in toothpaste manufacture.

Example 1

The silicas used in comparative example 1 were blended together withtitanium dioxide in the following matrix, which includes the individualsilicas with TiO₂ :

    ______________________________________             Comp.  Comp.   Comp.   Comp. Comp.             1      2       3       4     5             parts  parts   parts   parts parts             by wt  by wt   by wt   by wt by wt    ______________________________________    SORBOSIL TC15               97.0     72.75   48.5  24.25 0    (*)    SORBOSIL AC77               0        24.25   48.5  72.75 97.0    (*)    TiO.sub.2  3.0      3.0     3.0   3.0   3.0    ______________________________________     (*)-obtainable from Joseph Crosfield & Sons  England

De-ionised water was added to the powder mixes to give a water:solidsratio of 1.33 to 1 and the resulting 200 g blends were agglomeratedusing a laboratory scale Sirman CV6 mixer, supplied by Metcalfe CateringEquipment Ltd, Blaenau Ffestiniog, Wales.

The resulting wet agglomerates were then dried in an oven at 150° C. for4 hours, gently forced through a 420 micron screen and sieved at 150microns to adjust the particle size distribution.

The resultant agglomerates have the following properties:

    ______________________________________              Ultrasonics                      d10       d50    d90    ______________________________________    Composition 1                0         258       404  555                50        254       389  547                100       128       309  500    Composition 2                0         228       370  542                50        201       355  530                100       118       277  474    Composition 3                0         207       351  534                50        167       320  509                100       5.3       73   220    Composition 4                0         176       324  506                50        4         15.6 71                100       3.4       11   29.8    Composition 5                0         8.8       186  332                50        2.8       9.4  31.6                100       2.6       8.3  21.1    ______________________________________

Compositions 1 & 5 show that the addition of TiO₂ has no detrimentaleffect on particle strength of the agglomerate. It can be seen thatparticle strength varies according to the relative amounts of high andmedium/low structure silicas present in the agglomerate. Compositions 1& 2 are considered to be too strong and compositions 4 & 5 too weak foran optimum strength granule. Composition 3, whilst not optimum isconsidered to be within the desired range for strength.

Example 2

The following powders were blended together to give an intimate mixture:

    ______________________________________                 1        2                 parts by weight                          parts by weight    ______________________________________    Sorbosil AC77 (*)                   43.15      48.5    Sorbosil TC15 (*)                   43.15      48.5    Titanium Dioxide                   3.0        3.0    Zinc citrate trihydrate                   10.7       0    ______________________________________     (*)-obtainable from Crosfield Limited  England

Water was added to this mixture to give a water:solids ratio of 1.33 to1, the resulting blend being granulated in a 100 liter CMGmixer/granulator made by Eurovent Ltd, Fenton, Stoke-on-Trent, with a 6Kg batch charge.

The resulting wet agglomerates were then partially dried for 30 minutesin a fluid bed drier and finished in an oven for 2 hours at atemperature of 120° C. The particle size distribution was adjusted byscreening at 150 and 400 microns. The properties of the granularcomposition are outlined below.

    ______________________________________              Ultrasonics                      d10       d50    d90    ______________________________________    Composition 1                0         193       334  502                50        112       289  475                100       3.3       14.3 41.5    Composition 2                0         268       391  539                50        224       365  526                100       3.3       12   39    ______________________________________

Clearly, the presence of zinc citrate has little effect on the strengthof the granular compositions and granules of this strength have beenshown to survive the normal processing conditions used in toothpastemanufacture, be stable in and have good sensory properties in atoothpaste composition.

Examples 3-7

The following homogeneous powder blends were made:

    ______________________________________    INGREDIENT   EX 3    EX 4    EX 5  EX 6  EX 7    ______________________________________    SORBOSIL AC77                 41.0    36.0    24.5  40.3  47.85    SORBOSIL TC15                 41.0    36.0    24.5  13.4  47.85    TRICLOSAN    4.3                         4.3    STANNOUS             14.3    PYROPHOSPHATE    ZINC CITRATE 10.7    10.7    6.3    TRIHYDRATE    TITANIUM     3.0     3.0     3.0   3.0    DIOXIDE    POTASSIUM                    41.7    NITRATE    POTASSIUM                          43.3    CITRATE    ______________________________________

De-ionised water was added to the powder mixes (200 g) to give awater:solids ratio of 1.33 to 1 for examples 3, 4 & 7 and 0.72 to 1 forexamples 5 & 6. The resulting blends were agglomerated using alaboratory scale Sirman CV6 mixer, supplied by Metcalfe CateringEquipment Ltd, Blaenau Ffestiniog, Wales. The resulting wet agglomerateswere then dried in an oven at 150° C. for 12 hours, gently forcedthrough a 420 micron screen and sieved at 150 microns to adjust theparticle size distribution.

The resultant agglomerates have the following properties:

    ______________________________________            Ultrasonics                    d10        d50    d90    ______________________________________    Example 3 0         186        306  488              50        14         222  425              100       3.8        23   62    Example 4 0         223        385  530              50        9.4        151  423              100       4          16   41    Example 5 0         32         233  460              50        11         128  376              100       3.9        17   45    Example 6 0         199        386  554              50        8          180  412              100       3          13   41    Example 7 0         190        346  532              50        30         286  510              100       4          16   46    ______________________________________

Examples 8-10

The following homogeneous powder blends were made:

    ______________________________________    INGREDIENT    EX 8        EX 9   EX 10    ______________________________________    SORBOSIL AC77 26.3        43.1   60.0    SORBOSIL TC15 26.3        43.1   40.0    POTASSIUM     24.6    PYROPHOSPHATE    SODIUM        19.8    PYROPHOSPHATE    ZINC CITRATE              10.8    TRIHYDRATE    TITANIUM DIOXIDE                  3.0         3.0    ______________________________________

The powder blends were fed through a roller compactor Fitzpatrick.Chilsonator model L83 (made by Fitzpatrick Company, Elmhurst, Ill., USA)which was configured as FIG. 1 in the article "Preconditioning processpowders with dry granulation" by Calvin E. Johnson (The FitzpatrickCompany), cited in Powder and Bulk Engineering December 1987. The upperscreen size was 425 microns and the lower one was 250 microns.

The resultant agglomerated product had the following properties:

    ______________________________________             Ultrasonics                     d10        d50    d90    ______________________________________    Example 8  0         150        326  526               50        17         162  383               100       4          29   69    Example 9  0         176        331  530               50        74         292  516               100       6.9        72   314    Example 10 0         160        300  497               50        120        288  495               100       3          15   69    ______________________________________

Examples 11-14

The following homogeneous powder blends were made:

    ______________________________________    INGREDIENT   EX 11    EX 12    EX 13  EX 14    ______________________________________    GASIL 23D             72.75    36.0   64.9    GASIL 23TP   50.0    SORBOSIL AC35         24.25    12.0   21.6    GASIL 200TP  50.0    TITANIUM DIOXIDE      3.0      2.6    2.6    POTASSIUM                      43.3    CITRATE    ZINC CITRATE                   6.1    10.9    TRIHYDRATE    ______________________________________

De-ionised water was added to the powder mixes (200 g) to give awater:solids ratio of 1.33 to 1 for examples 11,12 & 14 and 0.72 to 1for example 13. The resulting blends were agglomerated using alaboratory scale Sirman CV6 mixer, supplied by Metcalfe CateringEquipment Ltd, Blaenau Ffestiniog, Wales.

The resulting wet agglomerates were then dried in an oven at 150° C. for12 hours, gently forced through a 420 micron screen and sieved at 150microns to adjust the particle size distribution.

The resultant agglomerates have the following properties:

    ______________________________________             Ultrasonics                     d10       d50    d90    ______________________________________    Example 11 0         197       354  526               50        10        213  465               100       3.3       15   50    Example 12 0         187       311  498               50        16        250  471               100       5         34   297    Example 13 0         190       333  518               50        14        210  455               100       4         24   69    Example 14 0         196       326  514               50        96        282  476               100       4         29   104    ______________________________________

Examples 15-16

The following homogeneous powder blends were made:

    ______________________________________    INGREDIENT           EX 15   EX 16    ______________________________________    BACO AF239           50.0    CALCIUM PYROPHOSPHATE        50.0    SORBOSIL TC15        50.0    50.0    ______________________________________

De-ionised water was added to the powder mixes (200 g) to give awater:solids ratio of 1.33 to 1. The resulting blends were agglomeratedusing a laboratory scale Sirman CV6 mixer, supplied by Metcalfe CateringEquipment Ltd, Blaenau Ffestiniog, Wales.

The resulting wet agglomerates were then dried in an oven at 150° C. for12 hours, gently forced through a 420 micron screen and sieved at 150microns to adjust the particle size distribution.

The resultant agglomerates have the following properties:

    ______________________________________             Ultrasonics                     d10       d50    d90    ______________________________________    Example 15 0         219       379  536               50        194       355  524               100       6.7       43   186    Example 16 0         215       373  534               50        177       339  517               100       3         37   95    ______________________________________

Examples 17-19

The following blends were made:

    ______________________________________    INGREDIENT      EX 17     EX 18   EX 19    ______________________________________    SORBOSIL AC77   44.2      43.9    44.45    SORBOSIL TC15   44.1      43.9    44.45    ZINC CITRATE    11.0      10.7    11.76    TRIHYDRATE    COSMENYL BLUE A2R                    0.7               0.07    COSMENYL GREEN GG                 0.27    COSMETIC PINK RC 01       1.5    ______________________________________

De-ionised water was added to the powder mixes (200 g) to give awater:solids ratio of 1.33 to 1. With examples 17 & 19, the Cosmenylpigment dispersions were added to the de-ionised mixing water, which wasthen added to the powder mix. The resulting blends were agglomeratedusing a laboratory scale Sirman CV6 mixer, supplied by Metcalfe CateringEquipment Ltd, Blaenau Ffestiniog, Wales.

The resulting wet agglomerates were then dried in an oven at 150° C. for12 hours, gently forced through a 420 micron screen and sieved at 150microns to adjust the particle size distribution.

The resultant agglomerates have the following properties:

    ______________________________________              Ultrasonics                      d10       d50    d90    ______________________________________    Example 17  0         182       301  487                50        41        251  447                100       4         22   62    Example 18  0         191       344  532                50        163       347  534                100       5.6       39   210    Example 19  0         192       345  537                50        77        285  511                100       4         19   49    ______________________________________

Example 20

A toothpaste having the following composition was produced.

    ______________________________________    INGREDIENT        % BY WEIGHT    ______________________________________    Sorbitol          45    Water             22.12    Sorbosil AC77     10.0    Silica of the Invention                      7.0    Sorbosil TC15     6.0    PEG 1500          5.0    SLS               1.5    TiO.sub.2         1.0    Spearmint Flavour DP5017                      0.5    SMPF              0.8    SCMC              0.8    Saccharin         0.2    Sodium Benzoate   0.08    ______________________________________

The above formulation was made under vacuum using conventionalpreparative procedures in a Lang mixer. In preparation 1 the flavorcomponent was added over the side of the vessel near the end of theformulation.

A further identical preparation 2 was carried out except that the flavorwas added to the silica granule of the invention by pipette prior to itsintroduction to the toothpaste mixer. The granule of the invention,containing the flavor, was dry mixed with the other two silicas and theresultant powder mix was added in portions over 40 minutes under closedvacuum.

The two pastes were then examined "blind" by 6 people, who were asked toassess the taste properties. All 6 people stated that paste 2 had asignificantly stronger spearmint taste than paste 1, indicating that thegranule of the invention could carry and deliver flavor more effectivelythan simply adding it to the toothpaste mix separately.

I claim:
 1. Granular composition comprising 45 to 98% w/w of a waterinsoluble particulate, whereby 10 to 75% of the water insolubleparticulate comprises a water insoluble particulate material having aweight mean particle size of less than 20 microns and an oil absorptioncapacity of 60 to 180 g/100 g, and is selected from the group consistingof amorphous silicas, aluminas, calcium carbonates, dicalcium phosphate,tribasic calcium phosphates, insoluble sodium metaphosphate, calciumpyrophosphates, hydroxyapatites, perlites, zeolites, magnesiumcarbonate, pumice, and 10 to 75% of the water insoluble particulatecomprises a water insoluble particulate material having a weight meanparticle size of below 20 microns and an oil absorption 200 to 350 g/100g, selected from the group consisting of amorphous silicas, low densityaluminas and expanded perlites, the granular composition having aparticle size, by sieve analysis, of 95% below 600 microns and 95% above40 microns.
 2. Granular composition according to claim 1 comprising 1 to5% w/w of TiO₂.
 3. Granular composition according to claim 1 comprisingup to 15% zinc citrate.
 4. Granular composition according to claim 1wherein the agglomerate contains a material having a cosmetic ortherapeutic dental benefit.
 5. Granular composition according to claim 1wherein the material having a cosmetic or therapeutic benefit is aflavor compound.
 6. Granular composition according to claim 1 comprisinga high structure silica thickener and a low structure silica abrasive.7. Process for producing a granular composition according to claim 1wherein, 10 to 75 parts by weight of a water insoluble particulatematerial, having a weight mean particle size of less than 20 microns andan oil absorption capacity of 60 to 180 g/100 g, and selected from thegroup consisting of amorphous silicas, aluminas, calcium carbonates,dicalcium phosphate, tribasic calcium phosphates, insoluble sodiummetaphosphate, calcium pyrophosphates, hydroxyapatites, perlites,zeolites, magnesium carbonate, pumice are mixed with 10 to 75 parts byweight of a water insoluble particulate material, having a weight meanparticle size of below 20 microns and an oil absorption 200 to 350 g/100g, selected from the group consisting of amorphous silicas, low densityaluminas and expanded perlites, then agglomerated with water, theresulting product being then dried.
 8. Process for producing a granularcomposition wherein, 10 to 75 parts by weight of a water insolubleparticulate material, having a weight mean particle size of less than 20microns and an oil absorption capacity of 60 to 180 g/100 g, andselected from the group consisting of amorphous silicas, aluminas,calcium carbonates, dicalcium phosphate, tribasic calcium phosphates,insoluble sodium metaphosphate, calcium pyrophosphates, hydroxyapatites,perlites, zeolites, magnesium carbonate, pumice are mixed with 10 to 75parts by weight of a water insoluble particulate material, having aweight mean particle size of below 20 microns and an oil absorption 200to 350 g/100 g, selected from the group consisting of amorphous silicas,low density aluminas and expanded perlites, the resulting blend beingagglomerated by compaction.
 9. Process according to claim 7 or 8 whereinTiO₂ and zinc citrate is added to the amorphous silica particles priorto agglomeration.
 10. Process according to claim 7 wherein theagglomeration with water is done with a water:solids ratio of 1.1:1 to1.35:1.